what is the type of crustal structure is this
BCC
APF=0.68
iron cold 910 deggre
What is the type of crystal structure is this
FCC
APF=0.74
iron over 910 deggre
Aerated Blocks
No agggregate Blocks
FRP is reinforced mainly by
glass fiber, carbon fiber
The molten materials are floated on
molten tin
Brosilicate added to
improve thermal resistance
The 3D unite of crystal structure is called
Lattice
polymers are
semi-crystallised material
Main property of the amorphous material is
Transparent
what is the main step in cooling and grinding the cement
Adding a gypsum
What is the name of the resulted product from the kiln stage of cement manufacture
clinker
The hydration process is exothermic process
true
exothermic process means
that this process produce heat
Additives
material used to replace part of the cement
Aggregate reduce the concrete cost
True
The aggregate that used for heavy weight concrete are
Magnetate and lead
in the Uk the percentage of seconary and recycled aggregate used is
29%
good grading of different use of concrete is controlled by whaich British standerds
BS882
the percentage of primary aggregates used for concrete in the uk is
71%
which of the following are admixtures
Accelerators, retarders, plasticiser
accelerators are prohibited to be used in
steel reinforced concrete
concrete mix design method
nominal mix, standard mix, DoE mix
which element is the easiest to be compacted
slabs
workability test
slamp test, compactability test, flow table test
what is not the meaning of consistency
cohesiveness
What are the reasens behind early sets
insufficient gypsum, incorrect gypsum time
what the main reasons of plastic settlement
the existence of restrains (steel or narrow section)
steel links are used to resist
shear stress
the more aggregates, the more shrinkage
False
Concrete stiffness increases when w/c increases
What is the main reasons for visual deterioration
chemical material, lack of supervision, bad implement
what are the main chemical attacks of cement
sulphate, sea water and acid
the main characteristics of pure metals are
soft and ductile
select the metals advantages
the can be alloyed and welded,
the are soft and ductile,
they are not porous
phase digram show the relationship between metal composition and passure
false
the same atom size for the mixed materials, the more complex phase diagram
how many phase we have when we mix lead with tin
6
what is the main alloyed element to iron
carbon
what the maximum carbon content iron should have to still be able to be used in construction
6%
the different between steel and cast iron is the carbon content
Ture
the maximum carbon content in steel is
2%
what are the main iron inside iron- carbon phase digram to remember
Austente (gamma) iron,
ferrite (Aipha) iron,
Austenite in liquid,
cement
when Gama iron is cooled slowly to under 723 degrees, it transfers to
Pearlite
the process of the transformation of Gama to perlire is called
Eutectord
the main components of high carbon steel are
cementite and pearlite
the main properties of pearlite are
hard and brittle
which heat treatment is applied on a high carbon steel
Spheroidise Annealing
Full Annealing mean cooling Gama iron by air
False, extremely slowly in kiln
in steel work hardeing
we load the steel to exceed yield strength
quenched steel is called
martensite
what is the colour of pure iron
Gray
intrational definition of iron, pig iron is
iron with carbon content of 3.5-4.5% and other impurities
alloy steel is a steel alloyed with carbon only
false, carbon and other significant alloying elements up to 50% such as chromium
the main raw materials for iron production are
limestone,
iron ore,
coke
the most used type of ore is
Hematite
the fuctory that is used for iron production, is called
Blast furnace
iron oxide and carbon react to produce
cemente
cast iron is produced from
pig iron
wrought iron is iron with high carbon content
puddled wrought iron is more expensive then wrought iron
The element we add to transfer the pig iron to steel is
oxygen
basic oxygen steel making is developed from which technique
Bassemer steel
What are the two main issues to consider for iron/steel durability
Mill scale and rusting
what process that causes mill scale
hot working
what are the basic components of structure steel
iron
magniziam
what raw materials are required for steel to be created
iron ore
limeston
what are the bolts types
HSFG bolts
non-preloaded bolts
what are the two types of non preloaded bolts
Grad 8.8
Gead 4.6
Weld metal should have in comparing with the mother metals
Lower ductile & higher yield
Heat affected zone HAZ should have
Lower carbon
How many types of weld inspection are stated in the session
5
The way of bonding of phenol-formaldenyde is
Random
Elastoeners can be used as
Gap filling
The main properties and the iron atoms arrangement for steel heated to 850 degrees care
tough
ductile
When testing the comressive strength of concrete cubes in the Maudslay concrete labs, what is the volume of each cube used
1,000,000 mm2
If a compressive strength test on a cube produced a maximum load of 387KN, what is the cube compressive strength
38.7 N/mm2
what type of polymer is HDPE
High Density polyethylene
The main properties and iron atom arrangment for steel quenched from Gamma phase are
Hard
Brittle
What is a bittle material
material which does not have,
or has very little,
plastic deformation
The larger the grain size, the harder the material
the more slip planes, the more brittle the material
Face centered cubic structures have more slip planes than body centred cubic BCC structure
Cast iron & Glass =
Steel and Nylon =
Cast iron & Glass = Brittle
Steel and Nylon = Ductile
What is yield strength
the stress where materials move from being clastic to plastic
What is the main reason for practical strength being less then theoretictical strength in metals
imperfection and defects
What is the ratio of the change of stress over the change of strain E called
Stiffness,
Modulus of elasticity,
young modulus
What are the main factors for metals rusting
water and air
what is a typical carbon content of structural steel
0.3% - 1.3%
which type of steel connection is not used anymore
Riveting
which the main raw materials used to produce steel
Limestone,
oxygen,
iron ore (Hematie),
Coke
When material are formed, the quicker it cools, the smaller the grain size
Brittle materials have longer critical crack length
what is the name of the material which Austenite turns to , by cooling slowly under 723 dgrees
which are NOT steps in a slump test
Ensure that each layer of concret is fully compacted,
measuare the slamp from the highest point of the concrete to the cone height to the nearest nearest 5mm
create visual observation of crushed specimens from hardened concrete tests can show the following
1-the rate of loading of the sample
2-wether the aggregate is well bonded
3- how well the sample was compacted
4-whether the concrete was well cured
Main three factors that affect the different mechanical properties of metals
Alloying
Heat treatment
their crystal structure
Hexagonal Close Packed (HCP)
Simple cubic (SC)
three materials that we use to produce cement.
Portland Cement types
Aggregates - By Wetness
Concrete compaction
Visual deformation
bad implement
Lack of supervision
water ingress (maintenance of drange)
Durability- Internal Deterioration
porosity
Acidic corrosion
timber defects- knots
timber durability- Agents
Aggregate in blocks
Surface cleaning
Concrete attack - Carbonation
Early age concrete
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